WO1995022580A1 - Aqueous compositions for the water repellent treatment of masonry - Google Patents

Aqueous compositions for the water repellent treatment of masonry Download PDF

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Publication number
WO1995022580A1
WO1995022580A1 PCT/AU1995/000085 AU9500085W WO9522580A1 WO 1995022580 A1 WO1995022580 A1 WO 1995022580A1 AU 9500085 W AU9500085 W AU 9500085W WO 9522580 A1 WO9522580 A1 WO 9522580A1
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WIPO (PCT)
Prior art keywords
siloxane
emulsion
carbon atoms
weight
water
Prior art date
Application number
PCT/AU1995/000085
Other languages
French (fr)
Inventor
Ren Kebao
Douglas Kagi
Original Assignee
Victoria University Of Technology
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Publication date
Application filed by Victoria University Of Technology filed Critical Victoria University Of Technology
Priority to AU18018/95A priority Critical patent/AU689224B2/en
Publication of WO1995022580A1 publication Critical patent/WO1995022580A1/en

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/009—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone characterised by the material treated
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
    • C04B41/46—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements with organic materials
    • C04B41/49—Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters ; Organo-phosphorus compounds; Organo-inorganic complexes
    • C04B41/4905—Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters ; Organo-phosphorus compounds; Organo-inorganic complexes containing silicon
    • C04B41/495—Compounds having one or more carbon-to-metal or carbon-to-silicon linkages ; Organo-clay compounds; Organo-silicates, i.e. ortho- or polysilicic acid esters ; Organo-phosphorus compounds; Organo-inorganic complexes containing silicon applied to the substrate as oligomers or polymers
    • C04B41/4961—Polyorganosiloxanes, i.e. polymers with a Si-O-Si-O-chain; "silicones"
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/60—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only artificial stone
    • C04B41/61—Coating or impregnation
    • C04B41/62—Coating or impregnation with organic materials
    • C04B41/64—Compounds having one or more carbon-to-metal of carbon-to-silicon linkages
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/80—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only ceramics
    • C04B41/81—Coating or impregnation
    • C04B41/82—Coating or impregnation with organic materials
    • C04B41/84—Compounds having one or more carbon-to-metal of carbon-to-silicon linkages
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00—Processes of treating or compounding macromolecular substances
    • C08J3/02—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques
    • C08J3/03—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D183/00—Coating compositions based on macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon, with or without sulfur, nitrogen, oxygen, or carbon only; Coating compositions based on derivatives of such polymers
    • C09D183/04—Polysiloxanes
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2383/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen, or carbon only; Derivatives of such polymers
    • C08J2383/04—Polysiloxanes

Definitions

  • the present invention relates to the treatment of materials to impart water repellency thereto. More particularly this invention relates to water repellent compositions containing aqueous emulsions of siloxanes and siloxanes/silanes for use on materials used in building.
  • Hydrophobic additives may be added to the building materials before they are formed, or the second alternative is to impregnate or coat the building materials after they are formed.
  • the present invention relates to a method of treating the building material after it has been formed to make it water repellent.
  • Organosilicone products dissolved in organic solvents have been used for rendering masonry and other substrates water repellent for many years.
  • the products in use are silanes, siloxanes or mixtures of silanes and siloxanes. These have been used in varying concentrations with or without catalysts.
  • pure silanes without the use of solvent carrier have been used as disclosed in U.S. Patent No. 4,716,051 to Rodder.
  • these products have been technically successful in terms of good penetration depth, low water absorption of the treated substrate and alkali stability of the final polymer.
  • Alkylalkoxysilanes have been used widely to impregnate permeable mineral building materials to render them water repellent.
  • the action of alkylalkoxysilanes in rendering a surface hydrophobic is known to be based on the fact that when an alkylalkoxysilane is applied onto the surface, the atmospheric moisture, and in some cases the water that is on the surface, causes the silane to be hydrolysed and alkyl silanols are formed as intermediates.
  • the hydroxyl groups of the silanol react with the hydroxyl groups of the material, and with other hydroxyl groups of silanols forming siloxanes.
  • a bond between alkyl siloxanes and the mineral boundary surface is produced in which the alkyl group of the siloxane is exposed on the surface.
  • This boundary surface bond greatly increases the surface tension of the mineral materials with respect to water, and the surface becomes water repellent.
  • the degree of the water repellency on the surface of the substrate depends on the nature of the alkyl group of the alkylalkoxysilane.
  • the bond between the alkyl group and the silicon atom of the silane can be destroyed by light and ultraviolet rays. For long term hydrophobicity, the silane should penetrate deeply into the surface to be protected from the destructive action of light and ultraviolet rays.
  • Aqueous silicone compositions have been developed in an attempt to overcome the problems of organic solvents and the alkalinity of organosiliconates.
  • U.S. Patent No. 2,881 ,146 to Remer et al. discloses an organopolysiloxane emulsion for the treatment of fabrics.
  • Hyde et al. in U.S. Patent No. 2,891 ,920 describe emulsions of organopolysiloxanes as protective coatings for surfaces as distinct from impregnating materials.
  • U.S. Patent No. 3,076,773 to Foster et al. describes aqueous emulsions of solvent/siloxane mixtures for the surface coating of metal plates and boxes.
  • U.S. Patent No. 3,294,725 to Findlay et al. discloses a method of preparing stable organopolysiloxane latex emulsions by polymerising siloxanes and silcarbanes, using a surface active sulfonic ' acid catalyst.
  • the emulsions produced by this method are very stable and have very fine particle sizes.
  • U.S. Patent 4,175,159 to Raleigh discloses a silicone emulsion for treating silicate particulate matter such as perlite and vermiculite.
  • This emulsion of a silicone polymer is produced with an emulsifier of the ammonium salt of a long chain aliphatic carboxylic acid.
  • the silicate particles are heated and the silicone fluid forms a coating on the silicate surface and the ammonia evaporates to leave the oily aliphatic carboxylic acid on the surface.
  • Koerner et al. in U.S. Patent No. 4,476,282 disclose a method of producing finely divided oil-in-water emulsions of organopolysiloxanes.
  • U.S. Patent No. 4,552,910 to Deubzer et al. discloses aqueous organopolysiloxane emulsions for use as additives in aqueous paint compositions.
  • Grape et al. in U.S. Patent No. 4,582,874 disclose a method of preparation of aqueous emulsions of low molecular weight silicone resins with non-ionic emulsifiers or two non-ionic emulsifiers.
  • Liles et al. in U.S. Patent No. 5,074,912 disclose a siloxane emulsion as a masonry water repellent where the siloxane molecule of the silylidyne radical is present.
  • An emulsion of a polysiloxanediol, an aminosilane, a higher alkylsilane and a mixture of non-ionic surfactants is disclosed in E.P. 0 476 452 A2 to Seyffert ' et al.
  • U.S. Patent No. 5,091 ,002 to Schamberg et al. discloses a composition which comprises an emulsion of an alkoxysilane, an emulsion of a polysiloxane, a non-ionic or anionic surfactant and a filler.
  • Gerhardinger et al. discloses an emulsion of a silane and siloxane to impregnate paper-containing building material.
  • the use of surfactants may result in a poor beading effect, possibly due to the adsorbed surfactant at the surface undergoing rewetting on exposure to water.
  • an emulsifier is usually necessary.
  • the emulsifier has an effect on the masonry surface which deteriorates the water repellent effect of the treated surface. This effect causes a wetting of the very surface of the substrate and therefore would not be acceptable in freezing climatic conditions.
  • pollutive substances could be carried into the substrate in this wetted layer.
  • the present invention provides long shelf stable siloxane emulsions and siloxane/silane emulsions with surfactants as the emulsifiers.
  • long-shelf stable means that the emulsions are capable of being stored for at least three months under normal storage conditions without separating or undergoing gelling.
  • the present invention aims to produce long shelf stable aqueous silicone emulsions.
  • the use of these emulsifiers overcomes the problem of prior art emulsions where the treated surface is wettable.
  • an advantage of the emulsions of the present invention is that it has been found that the penetration depth of the emulsions prepared by the method of this invention is considerably higher than that obtained by similar compositions of the prior art.
  • Another advantage of the emulsions prepared by the method of this invention is that the emulsions may contain no solvent and they can be considered as environmentally friendly products which comply with the volatile organic compound (VOC) regulations.
  • VOC volatile organic compound
  • hydrolysable alkylalkoxysiloxane having the general formula:
  • R represents a hydrocarbyl group containing from 1 to 30 carbon atoms
  • b is 0, 1 or 2
  • R' represents an aliphatic group containing from 1 to 10 carbon atoms
  • a surfactant selected from the group consisting of an alkylamine alkoxylate, an acidified or partially acidified alkylamine alkoxylate, quaternary alkyl ammonium salts, acid alkylamine salts and imidazoline salts; and 50% to 98% by weight of water.
  • the invention also provides an aqueous siloxane/silane emulsion as described above further comprising up to 45% by weight of an alkylalkoxysilane of the general formula
  • the present invention also provides a method of making aqueous siloxane and siloxane/silane emulsions comprising effective amounts of: (1 ) a hydrolysable siloxane, (2) optionally a hydrolysable silane, (3) a surfactant which is an alkylamine alkoxylate and (4) water. Solvent may additionally be added in this method. However, this is not necessary or desirable in most cases.
  • the present invention also provides a process for achieving water repellency for permeable masonry by applying to the surface of the permeable substrate a composition containing the emulsion as above defined and allowing the composition to cure.
  • masonry means any permeable inorganic substrate that consists of or contains constituents capable of reacting with siloxanes or silanes.
  • Masonry materials containing hydroxy groups or metal oxides can react with siloxanes or silanes so that a siloxane film can be formed in the surface capillaries.
  • the building materials best fulfilling these requirements are concrete, light clinker and light ballast concrete, lightweight concrete, mortars, plaster of Paris and products prepared from gypsum, fibre cement, materials and products prepared from fired or sintered clay, ballast and fibre containing silica or glass.
  • the emulsions prepared by the method of this invention are useful for rendering any permeable substrates that possess latent alkalinity or latent catalytic activity, water repellent. It is believed that the latent alkalinity of such substrates promotes the hydrolysis and condensation of the alkylalkoxysilane and alkylalkoxysiloxane into a resinous silicone matrix which is permanently formed and deposited within the interior capillaries of the substrates.
  • the masonry to be treated with the water repellent compositions in this invention is preferably dry, although it may be somewhat wet.
  • the hydrolysable alkoxysiloxanes (1 ) useful in the method of this invention generally have an average molecular weight in excess of 300 and up to about 3000. It should be noted that mixtures of various siloxanes may be used, if desired.
  • the preferred hydrolysable alkoxysiloxane having the general formula: R Si(OR') b O 3 . b
  • R is C-, - C 30 hydrocarbyl, or halogenated hydrocarbyl group and R' is a C-, - C 6 alkyl group.
  • the hydrocarbyl group may be alphatic, or cyloaliphatic, or aralkyi, or aryl. This hydrocarbyl group may also contain one or more halogen substituents, and/or nitrogen oxygen or sulfur hetero atoms.
  • R is preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, nonyl or decyl.
  • the R groups attached to silicon will contain a proportion of alkyl with more than three carbon atoms.
  • R' is preferably a methyl or ethyl group.
  • the hydrolysable alkylalkoxysilanes (2) useful in the method of this invention generally have an average molecular weight in excess of 135 and preferably greater than 190 up to about 600 for the monomers. It should be noted that mixtures of various silanes may be used, if desired.
  • the preferred hydrolysable alkylalkoxysilane (2) having the general formula:
  • R" n - Si - R" n ID wherein R" is a C, - C 30 hydrocarbyl, or halogenated hydrocarbyl group and R'" is a C, - C 6 alkoxy group, and n is 1 or 2.
  • the hydrocarbyl group may be aliphatic, or cycloaliphatic, or aralkyi, or aryl. These hydrocarbyl radicals may also contain one or more halogen substituents, and/or nitrogen, oxygen or sulfur hetero atoms.
  • R" is preferably propyl, butyl, pentyl, hexyl, octyl, nonyl or decyl.
  • R" will contain more than three carbon atoms.
  • R'" is preferably a methoxy or ethoxy group and most preferably an ethoxy group.
  • Silanes that are useful in accordance with the present invention include, but are not limited to: methyltrimethoxysilane, butyltriethoxysilane, octyltriisopropoxysilane, methyltriethoxysilane, n-hexyltrimethoxysilane, 2-ethylhexyltrimethoxysilane, methyltri-n-propoxysilane, 6-chlorohexyltrimethoxysilane,
  • the emulsions prepared by the method of this invention consist of one to about fifty percent by weight of the mixtures of alkylalkoxysiloxanes and alkylalkoxysilanes or mixtures of silanes, and preferably the emulsions include two to fifty percent by weight of the mixture of siloxanes and silanes.
  • the siloxane component (1 ) is present in an amount of from about 10 to 100 parts by weight and the silane component (2) is present in from about 0 to 90 parts by weight of the total siloxane/silane mixture.
  • part of the silane component may be substituted by aliphatic solvent.
  • the surfactant (3) is also included.
  • ionic and non-ionic surfactants are unable to achieve a satisfactorily stable emulsion with good penetration effect on substrates and good surface beading effect.
  • the surfactants useful in the present invention which achieve these effects are surfactants such as alkylamine alkoxylates, quaternary alkyl ammonium salts, and alkylamine and imidazoline salts.
  • Alkylamine ethoxylates that are useful in accordance with the present invention include, but are not limited to: Ethoxylated long chain amines
  • Alkyl polyamine ethoxylates Alkyl polyoxyethylene amines Ethoxylated amines Fatty amine ethoxylates Polyoxyethylated fatty amines
  • alkylamine ethoxylate surfactants which may be used in accordance herewith include, but are not limited to the following: - Terics 12M2, 12M5, 12M1 5, 13M15, 16M2, 16M5,
  • the surfactants other than alkylamine alkoxylates are able to be used when alkylalkoxysilanes are present in the emulsions, when only alkylalkoxysiloxanes are present these other surfactants are not recommended for use.
  • Quaternary ammonium surfactants which may be employed in the present invention include, but are not limited to: Cetyltrimethylammonium chloride - Vantoc CC30 Cetyltrimethylammonium bromide - Vantoc N40
  • alkylamine alkoxylates as surfactants in this invention is that this kind of surfactant will be deactivated and cause no wetting effect of the final treated surface when the emulsion is applied onto masonry surfaces. This is due to the positively charged nitrogen reacting with the negatively charged substrate surface to leave its hydrocarbon group oriented towards the surface. In addition, by adjusting the level of acid, a proper HLB for the surfactant for the system may be obtained. Within the protonated alkylamine ethoxylate there is exhibited both cationic surfactant properties and non-ionic surfactant properties in the one emulsifier.
  • the emulsions prepared by the method of this invention consist of 0.1 to about 10 percent by weight of the emulsifier, and preferably the emulsions include from 1 to about 5 percent by weight of the emulsifier.
  • the emulsions prepared by the art of the present invention are very stable and have extremely fine particle sizes.
  • the emulsions also have a long shelf life and can be diluted to any appropriate concentration without changing their stability.
  • the total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C.
  • the final emulsion contained 50% silicone by weight. It was milky white and stable and had an average particle size of 1 .1 5 urn.
  • EXAMPLE II 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 9.00 Grams of a methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Kunststoff) was mixed with 3.00 grams of isobutyltriethoxysilane as the organic phase.
  • BS1268 methoxy octyl/methyl siloxane
  • the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 1 3,500 rpm.
  • the total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C.
  • the final emulsion contained 50% silicone by weight. It was milky white and stable and had an average particle size of 0.60 um.
  • EXAMPLE III 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Kunststoff) was mixed with 6.00 grams of isobutyltriethoxysilane as the organic phase.
  • the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm.
  • the total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C.
  • the final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 0.45 um.
  • EXAMPLE IV 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 3.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Kunststoff) was mixed with 9.00 grams of isobutyltriethoxysilane as the organic phase.
  • the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm.
  • the total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C.
  • the final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size similar to that of example III.
  • EXAMPLE V 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 9.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie
  • EXAMPLE VI 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Kunststoff) was mixed with 6.00 grams of octyltriethoxysilane as the organic phase.
  • the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm.
  • the total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C.
  • the final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 0.47 um.
  • EXAMPLE VII 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 1 6M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 3.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Kunststoff) was mixed with 9.00 grams of octyltriethoxysilane as the organic phase.
  • EXAMPLE X 0.24 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.76 grams of water in a cylindrical flask. 10% Acetic acid was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Kunststoff) was mixed with 6.00 grams of octyltriethoxysilane as the organic phase.
  • BS1268 methoxy octyl/methyl siloxane
  • the final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 0.56 um.
  • EXAMPLE XI 0.06 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.94 grams of water in a cylindrical flask. 10% Acetic acid was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Kunststoff) was mixed with 6.00 grams of octyltriethoxysilane as the organic phase.
  • the substrate was cured for at least 7 days (the substrate achieves a constant weight).

Abstract

Aqueous siloxane and siloxane/silane emulsions are provided together with a method of providing them. The aqueous siloxane emulsion prepared in accordance with the invention comprises: (i) hydrolysable alkylalkoxysiloxane having general formula (I), wherein R represents a hydrocarbyl group containing from 1 to 30 carbon atoms, b is 0, 1 or 2, and R' represents an aliphatic group containing from 1 to 10 carbon atoms, (ii) 0,1 % to 10 % by weight of a surfactant selected from the group consisting of an alkylamine alkoxylate, or, an acidified or partially acidified alkylamine alkoxylate, quaternary alkyl ammonium salts, acid alkylamine salts and imidazoline salts; and (iii) water. The invention also provides that up to 45 % by weight of the emulsion may be alkylalkoxysilane of the formula: R'n - Si - R'''4-n wherein R' is a hydrocarbyl group containing from 1 to 20 carbon atoms, R''' is a hydrolysable group, and n is 1 or 2. These emulsions maintain high effective levels of the active silicone content on long term storage. The emulsions of the invention are useful in rendering permeable mineral substrates water repellent.

Description

AQUEOUS COMPOSITIONS FOR THE WATER REPELLENT TREATMENT OF MASONRY
The present invention relates to the treatment of materials to impart water repellency thereto. More particularly this invention relates to water repellent compositions containing aqueous emulsions of siloxanes and siloxanes/silanes for use on materials used in building.
There are two distinct means of making building materials water repellent. Hydrophobic additives may be added to the building materials before they are formed, or the second alternative is to impregnate or coat the building materials after they are formed. The present invention relates to a method of treating the building material after it has been formed to make it water repellent.
Organosilicone products dissolved in organic solvents have been used for rendering masonry and other substrates water repellent for many years. The products in use are silanes, siloxanes or mixtures of silanes and siloxanes. These have been used in varying concentrations with or without catalysts. In some instances pure silanes without the use of solvent carrier have been used as disclosed in U.S. Patent No. 4,716,051 to Rodder. In general, with the correct choice of active material, these products have been technically successful in terms of good penetration depth, low water absorption of the treated substrate and alkali stability of the final polymer.
Alkylalkoxysilanes have been used widely to impregnate permeable mineral building materials to render them water repellent. The action of alkylalkoxysilanes in rendering a surface hydrophobic is known to be based on the fact that when an alkylalkoxysilane is applied onto the surface, the atmospheric moisture, and in some cases the water that is on the surface, causes the silane to be hydrolysed and alkyl silanols are formed as intermediates. The hydroxyl groups of the silanol react with the hydroxyl groups of the material, and with other hydroxyl groups of silanols forming siloxanes. A bond between alkyl siloxanes and the mineral boundary surface is produced in which the alkyl group of the siloxane is exposed on the surface. This boundary surface bond greatly increases the surface tension of the mineral materials with respect to water, and the surface becomes water repellent. The degree of the water repellency on the surface of the substrate depends on the nature of the alkyl group of the alkylalkoxysilane. The bond between the alkyl group and the silicon atom of the silane can be destroyed by light and ultraviolet rays. For long term hydrophobicity, the silane should penetrate deeply into the surface to be protected from the destructive action of light and ultraviolet rays.
Solutions of silanes in various solvents such as alcohols, or hydrocarbons, have been employed for treating masonry surfaces for many years. However, the solvents used to carry the active material to the substrate are generally flammable or inflammable and have become increasingly expensive. In addition, the odour, environmental effects and the physiological effects of organic solvents are important factors against the use of organic solvent-based products. In various countries there is now legislation in place limiting the use of organic solvents. Therefore, there is an increasing demand for water repellent materials which may be delivered to the substrate in water and where the penetration into the substrate and performance of the treated substrate is similar to that achieved with organic solvent-based materials. Water-based materials in the form of the alkali metal organosiliconates have been used for many years. These solutions are highly alkaline and are therefore difficult to handle and are corrosive. In addition, the alkali metal methylsiliconates are not suitable for the treatment of alkaline substrates containing free lime and having a pH of 8 or more.
Aqueous silicone compositions have been developed in an attempt to overcome the problems of organic solvents and the alkalinity of organosiliconates.
U.S. Patent No. 2,881 ,146 to Remer et al., discloses an organopolysiloxane emulsion for the treatment of fabrics. Hyde et al. in U.S. Patent No. 2,891 ,920 describe emulsions of organopolysiloxanes as protective coatings for surfaces as distinct from impregnating materials. U.S. Patent No. 3,076,773 to Foster et al. describes aqueous emulsions of solvent/siloxane mixtures for the surface coating of metal plates and boxes.
U.S. Patent No. 3,294,725 to Findlay et al. discloses a method of preparing stable organopolysiloxane latex emulsions by polymerising siloxanes and silcarbanes, using a surface active sulfonic 'acid catalyst. The emulsions produced by this method are very stable and have very fine particle sizes.
U.S. Patent 4,175,159 to Raleigh discloses a silicone emulsion for treating silicate particulate matter such as perlite and vermiculite. This emulsion of a silicone polymer is produced with an emulsifier of the ammonium salt of a long chain aliphatic carboxylic acid. Following treatment of the silicate particulate matter, the silicate particles are heated and the silicone fluid forms a coating on the silicate surface and the ammonia evaporates to leave the oily aliphatic carboxylic acid on the surface.
Koerner et al. in U.S. Patent No. 4,476,282 disclose a method of producing finely divided oil-in-water emulsions of organopolysiloxanes. U.S. Patent No. 4,552,910 to Deubzer et al. discloses aqueous organopolysiloxane emulsions for use as additives in aqueous paint compositions. Grape et al. in U.S. Patent No. 4,582,874 disclose a method of preparation of aqueous emulsions of low molecular weight silicone resins with non-ionic emulsifiers or two non-ionic emulsifiers. R.P. Gee in U.S. Patent No. 4,620,878 discloses highly disperse organopolysiloxane emulsions. In U.S. Patent No. 4,661 ,551 Mayer et al. disclose transparent aqueous organopolysiloxane compositions which are microemulsions for use as hydrophobic agents for building materials and other uses. Sittenthaler et al. in U.S. Patent No. 4,833,187 disclose aqueous dispersions of organopolysiloxanes and ethylene-vinyl chloride copolymer for use in paint compositions. Australian Patent 71069/91 to Huhn et al. discloses highly disperse organopolysiloxane emulsions for various uses.
Liles et al. in U.S. Patent No. 5,074,912 disclose a siloxane emulsion as a masonry water repellent where the siloxane molecule of the silylidyne radical is present. An emulsion of a polysiloxanediol, an aminosilane, a higher alkylsilane and a mixture of non-ionic surfactants is disclosed in E.P. 0 476 452 A2 to Seyffert'et al. U.S. Patent No. 5,091 ,002 to Schamberg et al. discloses a composition which comprises an emulsion of an alkoxysilane, an emulsion of a polysiloxane, a non-ionic or anionic surfactant and a filler.
Cooper in U.S. Patent No. 5,1 10,684 discloses a masonry water repellent which consists of an emulsion including a siloxane molecule with the silylidyne radical.
E.P. 518,324 to Roth et al. discloses dispersions of silanes and siloxanes with nitrogen containing siloxanes. Ger Offen. DE
4,1 14,498 to Gerhardinger et al. discloses an emulsion of a silane and siloxane to impregnate paper-containing building material.
Ohashi in Jpn. Kokai Tokkyo Koho JP 05 32,784 discloses water soluble siloxanes with amine groups. Tagawa et al. in Jpn. Kokai Tokkyo Koho JP 06 128012 disclose polyorganosiloxanes emulsified with amines or quaternary ammonium salts. Existing organosiloxane emulsions and water soluble siloxanes do not compare well with existing solvent-based silanes, silane/siloxanes or siloxanes in terms of stability, penetration depth, and the beading effect of the treated substrate. In particular, the use of surfactants may result in a poor beading effect, possibly due to the adsorbed surfactant at the surface undergoing rewetting on exposure to water. In order to make an emulsion an emulsifier is usually necessary. However, what results is that the emulsifier has an effect on the masonry surface which deteriorates the water repellent effect of the treated surface. This effect causes a wetting of the very surface of the substrate and therefore would not be acceptable in freezing climatic conditions. In addition, pollutive substances could be carried into the substrate in this wetted layer. Therefore, it remains desirable to provide alternative aqueous water repellent siloxane and/or siloxane/silane emulsions without organic solvent additions which are stable, capable of effectively impregnating alkaline substrates and achieving a good water repellent effect.
The present invention provides long shelf stable siloxane emulsions and siloxane/silane emulsions with surfactants as the emulsifiers. The term "long-shelf stable" means that the emulsions are capable of being stored for at least three months under normal storage conditions without separating or undergoing gelling.
In one aspect the present invention aims to produce long shelf stable aqueous silicone emulsions. In addition the use of these emulsifiers overcomes the problem of prior art emulsions where the treated surface is wettable.
An advantage of the emulsions of the present invention is that it has been found that the penetration depth of the emulsions prepared by the method of this invention is considerably higher than that obtained by similar compositions of the prior art. Another advantage of the emulsions prepared by the method of this invention is that the emulsions may contain no solvent and they can be considered as environmentally friendly products which comply with the volatile organic compound (VOC) regulations. In accordance with the invention there is provided an aqueous siloxane emulsion comprising
5% to 50% by weight of hydrolysable alkylalkoxysiloxane having the general formula:
R Si(OR')bO3 , b
2 wherein R represents a hydrocarbyl group containing from 1 to 30 carbon atoms, b is 0, 1 or 2, and R' represents an aliphatic group containing from 1 to 10 carbon atoms,
0.1 % to 10% by weight of a surfactant selected from the group consisting of an alkylamine alkoxylate, an acidified or partially acidified alkylamine alkoxylate, quaternary alkyl ammonium salts, acid alkylamine salts and imidazoline salts; and 50% to 98% by weight of water.
In one embodiment, the invention also provides an aqueous siloxane/silane emulsion as described above further comprising up to 45% by weight of an alkylalkoxysilane of the general formula
R"n - Si - R'"4.n wherein R" is a hydrocarbyl group containing from 1 to 20 carbon atoms, R'" is a hydrolysable group, and n is 1 or 2.
In another aspect the present invention also provides a method of making aqueous siloxane and siloxane/silane emulsions comprising effective amounts of: (1 ) a hydrolysable siloxane, (2) optionally a hydrolysable silane, (3) a surfactant which is an alkylamine alkoxylate and (4) water. Solvent may additionally be added in this method. However, this is not necessary or desirable in most cases. The present invention also provides a process for achieving water repellency for permeable masonry by applying to the surface of the permeable substrate a composition containing the emulsion as above defined and allowing the composition to cure. When used herein, the term "masonry" means any permeable inorganic substrate that consists of or contains constituents capable of reacting with siloxanes or silanes. Masonry materials containing hydroxy groups or metal oxides can react with siloxanes or silanes so that a siloxane film can be formed in the surface capillaries. The building materials best fulfilling these requirements are concrete, light clinker and light ballast concrete, lightweight concrete, mortars, plaster of Paris and products prepared from gypsum, fibre cement, materials and products prepared from fired or sintered clay, ballast and fibre containing silica or glass. Generally, the emulsions prepared by the method of this invention are useful for rendering any permeable substrates that possess latent alkalinity or latent catalytic activity, water repellent. It is believed that the latent alkalinity of such substrates promotes the hydrolysis and condensation of the alkylalkoxysilane and alkylalkoxysiloxane into a resinous silicone matrix which is permanently formed and deposited within the interior capillaries of the substrates. The masonry to be treated with the water repellent compositions in this invention is preferably dry, although it may be somewhat wet. The hydrolysable alkoxysiloxanes (1 ) useful in the method of this invention generally have an average molecular weight in excess of 300 and up to about 3000. It should be noted that mixtures of various siloxanes may be used, if desired. The preferred hydrolysable alkoxysiloxane having the general formula: R Si(OR')bO3 . b
~ ~ (i) wherein R is C-, - C30 hydrocarbyl, or halogenated hydrocarbyl group and R' is a C-, - C6 alkyl group. The hydrocarbyl group may be alphatic, or cyloaliphatic, or aralkyi, or aryl. This hydrocarbyl group may also contain one or more halogen substituents, and/or nitrogen oxygen or sulfur hetero atoms.
In formula (I) R is preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, nonyl or decyl. To obtain good alkali stability of the final treated substrate, the R groups attached to silicon will contain a proportion of alkyl with more than three carbon atoms. R' is preferably a methyl or ethyl group.
The hydrolysable alkylalkoxysilanes (2) useful in the method of this invention generally have an average molecular weight in excess of 135 and preferably greater than 190 up to about 600 for the monomers. It should be noted that mixtures of various silanes may be used, if desired.
The preferred hydrolysable alkylalkoxysilane (2) having the general formula:
R"n - Si - R" n (ID wherein R" is a C, - C30 hydrocarbyl, or halogenated hydrocarbyl group and R'" is a C, - C6 alkoxy group, and n is 1 or 2. The hydrocarbyl group may be aliphatic, or cycloaliphatic, or aralkyi, or aryl. These hydrocarbyl radicals may also contain one or more halogen substituents, and/or nitrogen, oxygen or sulfur hetero atoms. In formula (II) R" is preferably propyl, butyl, pentyl, hexyl, octyl, nonyl or decyl. To obtain good alkali stability of the final treated substrate, R" will contain more than three carbon atoms. R'" is preferably a methoxy or ethoxy group and most preferably an ethoxy group. Silanes that are useful in accordance with the present invention include, but are not limited to: methyltrimethoxysilane, butyltriethoxysilane, octyltriisopropoxysilane, methyltriethoxysilane, n-hexyltrimethoxysilane, 2-ethylhexyltrimethoxysilane, methyltri-n-propoxysilane, 6-chlorohexyltrimethoxysilane,
4-chlorobenzyltrimethoxysilane, ethyltrimethoxysilane,
6,6,6-trifluorohexyltrimethoxysilane, decyltrimethoxysilane, ethyltriethoxysilane, cyclohexyltrimethoxysilane, dodecyltrimethoxysilane, dimethyldimethoxysilane,
4-bromobenzyltri-n-propoxysilane, dodecyltribromosilane, dimethyldiethoxysilane, phenyltrimethoxysilane, tetradecyltriethoxysilane, ethyltri-n-propoxysilane, phenyltriethoxysilane, hexadecyltriethoxysilane, propyltriethoxysilane, octyltrimethoxysilane, octadecyltriethoxysilane, propyltri-n-propoxysilane, octyltriethoxysilane, eicosyltrimethoxysilane, butyltrimethoxysilane, isooctyltriethoxysilane, isobutylmethoxysilane, isobutyltrimethoxysilane, isooctyltrimethoxysilane, di-isobutyldimethoxysilane, and the like.
The emulsions prepared by the method of this invention consist of one to about fifty percent by weight of the mixtures of alkylalkoxysiloxanes and alkylalkoxysilanes or mixtures of silanes, and preferably the emulsions include two to fifty percent by weight of the mixture of siloxanes and silanes.
In a preferred aspect of the invention the siloxane component (1 ) is present in an amount of from about 10 to 100 parts by weight and the silane component (2) is present in from about 0 to 90 parts by weight of the total siloxane/silane mixture. In addition part of the silane component may be substituted by aliphatic solvent. The surfactant (3).
A wide variety of ionic and non-ionic surfactants are unable to achieve a satisfactorily stable emulsion with good penetration effect on substrates and good surface beading effect. However, the surfactants useful in the present invention which achieve these effects are surfactants such as alkylamine alkoxylates, quaternary alkyl ammonium salts, and alkylamine and imidazoline salts. Alkylamine ethoxylates that are useful in accordance with the present invention include, but are not limited to: Ethoxylated long chain amines
Alkyl polyamine ethoxylates Alkyl polyoxyethylene amines Ethoxylated amines Fatty amine ethoxylates Polyoxyethylated fatty amines
Polyoxyethylene alkyl amines Specific examples of alkylamine ethoxylate surfactants which may be used in accordance herewith include, but are not limited to the following: - Terics 12M2, 12M5, 12M1 5, 13M15, 16M2, 16M5,
16M10, 16M15, 17M2, 17M5, 17M15, 18M2, 18M5, 18M10, 18M20, 18M30 (ICI Australia). The surfactants other than alkylamine alkoxylates are able to be used when alkylalkoxysilanes are present in the emulsions, when only alkylalkoxysiloxanes are present these other surfactants are not recommended for use.
Quaternary ammonium surfactants which may be employed in the present invention include, but are not limited to: Cetyltrimethylammonium chloride - Vantoc CC30 Cetyltrimethylammonium bromide - Vantoc N40
Benzyllauryldimethylammonium chloride - Vantoc CL80 (ICI Australia) The advantage of using the alkylamine alkoxylates as surfactants in this invention is that this kind of surfactant will be deactivated and cause no wetting effect of the final treated surface when the emulsion is applied onto masonry surfaces. This is due to the positively charged nitrogen reacting with the negatively charged substrate surface to leave its hydrocarbon group oriented towards the surface. In addition, by adjusting the level of acid, a proper HLB for the surfactant for the system may be obtained. Within the protonated alkylamine ethoxylate there is exhibited both cationic surfactant properties and non-ionic surfactant properties in the one emulsifier. In this way in general only one surfactant is necessary for the emulsions and a low volume of surfactant is required. The emulsions prepared by the method of this invention consist of 0.1 to about 10 percent by weight of the emulsifier, and preferably the emulsions include from 1 to about 5 percent by weight of the emulsifier.
The emulsions prepared by the art of the present invention are very stable and have extremely fine particle sizes. The emulsions also have a long shelf life and can be diluted to any appropriate concentration without changing their stability.
The following examples are set forth for the purpose of illustrating preferred aspects of the present invention. These examples are illustrative only and they are not to be constructed to limit the invention in any manner whatsoever. EXAMPLE I
0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 12.00 Grams of a methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was then added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 1 3,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 50% silicone by weight. It was milky white and stable and had an average particle size of 1 .1 5 urn.
EXAMPLE II 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 9.00 Grams of a methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was mixed with 3.00 grams of isobutyltriethoxysilane as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 1 3,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 50% silicone by weight. It was milky white and stable and had an average particle size of 0.60 um.
EXAMPLE III 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was mixed with 6.00 grams of isobutyltriethoxysilane as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 0.45 um.
EXAMPLE IV 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 3.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was mixed with 9.00 grams of isobutyltriethoxysilane as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size similar to that of example III.
EXAMPLE V 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 9.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie
GmbH Munich) was mixed with 3.00 grams of octyltriethoxysilane as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 0.50 um.
EXAMPLE VI 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was mixed with 6.00 grams of octyltriethoxysilane as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 0.47 um.
EXAMPLE VII 0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 1 6M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 3.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was mixed with 9.00 grams of octyltriethoxysilane as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 0.42 um. EXAMPLE VIII
0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was mixed with 6.00 grams of Exxsol D60 as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external 'cooling by tap water which was at approximately 20°C. The final emulsion contained 25% silicone by weight. It was milky white, stable and had an average particle size of 0.46 um. EXAMPLE IX
0.56 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.32 grams of water in a cylindrical flask. 10% Acetic acid solution was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was mixed with 6.00 grams of Isopar G as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 25% silicone by weight. It was milky white, stable and had an average particle size to that of 0.46 um.
EXAMPLE X 0.24 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.76 grams of water in a cylindrical flask. 10% Acetic acid was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was mixed with 6.00 grams of octyltriethoxysilane as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at speed of 13,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C.
The final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 0.56 um.
EXAMPLE XI 0.06 Grams of octadecylamine ethoxylates with two ethoxylate units (Teric 16M2) was added into 10.94 grams of water in a cylindrical flask. 10% Acetic acid was added to the flask to adjust the pH to approximately 7. Then water was added to make the total aqueous phase up to 12.00 grams. 6.00 Grams of methoxy octyl/methyl siloxane (BS1268 from Wacker-Chemie GmbH Munich) was mixed with 6.00 grams of octyltriethoxysilane as the organic phase. Then the organic phase was added dropwise into the aqueous phase during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 13,500 rpm. The total system was then shear mixed at the same speed for at least 10 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 1 .79 um. EXAMPLE XII 6.00 Grams of methoxy octyl/methyl siloxane (BS1 268 from Wacker-Chemie GmbH Munich) was mixed with 6.00 grams octyltriethoxysilane as an organic phase. 0.24 grams of octadecylamine ethoxylates with two ethoxylate units (Teric
1 6M2) was added into this organic phase with stirring. Then the organic mixture was added dropwise into a cylindrical flask containing 1 1 .76 grams of water during shear mixing with an Ultra-Turrax T25 shear mixer at a speed of 1 3,500 rpm. The total system was then shear mixed at the same speed for at least 1 0 minutes with external cooling by tap water which was at approximately 20°C. The final emulsion contained 50% silicone by weight. It was milky white, stable and had an average particle size of 2.59 um. Water Repellency Tests
Various building materials such as cement mortar discs and fired bricks were impregnated with such siloxane/silane emulsions. Surface beading effect, depth of impregnation and water absorption values were examined. The solvent-based siloxane impregnant (5% Wacker 290 in solvent Isopar G) was used as a control sample to compare with such emulsion impregnants. Depth of impregnation was examined according to the standard method. Surface beading effect was checked according to the following method:
After treatment the substrate was cured for at least 7 days (the substrate achieves a constant weight). A large drop of water (about 0.1 ml) was placed on the treated substrate surface for 1 0 minutes, and then the surface was checked according to the following scale: 1 = Excellent, no wetting of the surface
2 = Good. slight wetting of the surface (50% of the contact area is wet)
3 = Fair. wetting of the surface (100% of the contact area is wet)
4 = Poor. wetting and part absorption by the surface
(less than 50% absorbed)
5 = Bad. water drop partly absorbed (more than
50% absorbed) 6 = Very Bad. water drop completely absorbed
7 = No effect, no water drop is formed or it is absorbed within 5 minutes Water absorption for 7 days was examined by the sponge water absorption method according to DIN 52617. All substrates were impregnated by the impregnants for 1 minute. All the impregnants were diluted with distilled water to 5% by weight before impregnation.
Table 1 . Test results for treated cement mortar disc substrates (75X30 mm) which were prepared according to DIN 1 164 and cured for 7 days
Sample No. B Beeaading Effect Impregnation Water absorption depth (mm) (kg/m2)
Example I 2 0-1 0.54
Example III 1 -2 2 0.63 E Exxaammppllee VVII 1 1 --22 1 -2 0.54
Example VII 1 -2 2* 0.54
Example VIII 2 1 -2 0.55
Example IX 2 1 -2 0.58
Example X 1 -2 1 -2 0.63 W Waacckkeerr 229900 2 2 1 -2 0.66
Untreated Nil Nil 4.30 (1 day) * Depth of impregnation for commercial dense concrete impregnated with this emulsion at 20% concentration was 3.5 mm.
Table 2. Test results for treated fired brick substrates
(50X50X30 mm)
Sample No. Beading Effect Impregnation Water absorption depth (mm) (kg/m2)
Example I 3 6 0.34
Example III 2 6 0.01
Example VI 2-3 1 1 0.06
Example VII 1 4 0.04
Example VIII 2 3 0.49
Example IX 3 6 0.1 1
Example X 2 10 0.06
Wacker 290 1 13 0.02
Untreated Nil Nil 8.56

Claims

CLAIMS 1 . An aqueous siloxane emulsion comprising
5% to 50% by weight of hydrolysable alkylalkoxysiloxane having the general formula: R Si(OR')bO3 . b
wherein R represents a hydrocarbyl group containing from 1 to 30 carbon atoms, b is 0, 1 or 2, and R' represents an aliphatic group containing from 1 to 10 carbon atoms, 0.1 % to 10% by weight of a surfactant selected from the group consisting of an alkylamine alkoxylate, or, an acidified or partially acidified alkylamine alkoxylate, quaternary alkyl ammonium salts, acid alkylamine salts and imidazoline salts; and
50% to 98% by weight of water.
2. An emulsion as claimed in claim 1 further comprising up to 45% by weight of an alkylalkoxysilane of the general formula
Figure imgf000022_0001
wherein R" is a hydrocarbyl group containing from 1 to 20 carbon atoms, R'" is a hydrolysable group, and n is 1 or 2.
3. A siloxane or siloxane/silane emulsion as claimed in claim 1 or 2 wherein the alkylalkoxysiloxane has an average molecular weight between 300 and 3000.
4. A siloxane/silane emulsion as claimed in claim 2 wherein the alkylalkoxysilane has an average molecular weight between 135 and 600.
5. A siloxane or siloxane/silane emulsion as claimed in any one of the preceding claims wherein R is a hydrocarbyl group containing from 1 to 12 carbon atoms.
6. A siloxane or siloxane/silane emulsion as claimed in any one of the preceding claims wherein R' is an aliphatic group containing from 1 to 4 carbon atoms.
7. A siloxane or siloxane/silane emulsion as claimed in any one of the preceding claims and wherein R" is a hydrocarbyl group containing from 1 to 12 carbon atoms.
8. A siloxane or siloxane/silane emulsion as claimed in any one of the preceding claims wherein R'" is alkoxy.
9. A siloxane/silane emulsion as claimed in claim 2 wherein the alkylalkoxysilane is selected from the group consisting of octyltriethoxysilane; isobutyltriethoxysilane; isooctyltriethoxysilane; octyltrimethoxysilane; isobutyltrimethoxysilane; and, isooctyltrimethoxysilane.
10. A siloxane or siloxane/silane emulsion as claimed in claim 8 wherein R'" is methoxy or ethoxy.
1 1 . A siloxane or siloxane/silane emulsion as claimed in any one of the preceding claims wherein the surfactant is a partially acidified alkylamine ethoxylate.
12. A siloxane or siloxane/silane emulsion as claimed in any one of the preceding claims which additionally contains a biocidally effective amount of a biocide.
13. A method for treating permeable mineral building components comprising impregnating at least a surface of said permeable mineral building component with a composition as defined in any one of the preceding claims.
14. The product of the method defined in the preceding claim.
PCT/AU1995/000085 1994-02-21 1995-02-21 Aqueous compositions for the water repellent treatment of masonry WO1995022580A1 (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2749588A1 (en) * 1996-06-10 1997-12-12 Rhone Poulenc Chimie AQUEOUS EMULSION OF SILICONE RESIN FOR HYDROFUGATION OF CONSTRUCTION MATERIALS
EP2065431A1 (en) 2007-11-30 2009-06-03 Wacker Chemie AG Aqueous Dispersions of Organosilicon Compounds
US10829505B2 (en) 2016-04-20 2020-11-10 Dow Silicones Corporation Lithium alkylsiliconate composition, coating, and method of making same
WO2021126175A1 (en) 2019-12-18 2021-06-24 Wacker Chemie Ag Aqueous dispersions of organosilicon compounds

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4582874A (en) * 1983-07-02 1986-04-15 Bayer Aktiengesellschaft Silicone resin emulsion
US4648904A (en) * 1986-02-14 1987-03-10 Scm Corporation Aqueous systems containing silanes for rendering masonry surfaces water repellant
US4753977A (en) * 1986-12-10 1988-06-28 General Electric Company Water repellent for masonry
US4877654A (en) * 1988-05-02 1989-10-31 Pcr, Inc. Buffered silane emulsions for rendering porous substrates water repellent
US4940743A (en) * 1984-04-06 1990-07-10 Bayer Aktiengesellschaft Silicone resin emulsion
US5091002A (en) * 1989-04-08 1992-02-25 Th. Goldschmidt Ag Preparation for the water-repellent impregnation of porous mineral building materials
US5110684A (en) * 1990-11-07 1992-05-05 Dow Corning Corporation Masonry water repellent
AU1650392A (en) * 1991-05-03 1992-12-21 Wacker-Chemie Gmbh Emulsions of organopolysiloxane and alkyltrialkoxysilane for impregnating cement-bonded fibrous building components
US5393330A (en) * 1993-06-30 1995-02-28 Osi Specialties, Inc. Cationic emulsions of alkylalkoxysilanes

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4582874A (en) * 1983-07-02 1986-04-15 Bayer Aktiengesellschaft Silicone resin emulsion
US4940743A (en) * 1984-04-06 1990-07-10 Bayer Aktiengesellschaft Silicone resin emulsion
US4648904A (en) * 1986-02-14 1987-03-10 Scm Corporation Aqueous systems containing silanes for rendering masonry surfaces water repellant
US4648904B1 (en) * 1986-02-14 1988-12-06
US4753977A (en) * 1986-12-10 1988-06-28 General Electric Company Water repellent for masonry
US4877654A (en) * 1988-05-02 1989-10-31 Pcr, Inc. Buffered silane emulsions for rendering porous substrates water repellent
US5091002A (en) * 1989-04-08 1992-02-25 Th. Goldschmidt Ag Preparation for the water-repellent impregnation of porous mineral building materials
US5110684A (en) * 1990-11-07 1992-05-05 Dow Corning Corporation Masonry water repellent
AU1650392A (en) * 1991-05-03 1992-12-21 Wacker-Chemie Gmbh Emulsions of organopolysiloxane and alkyltrialkoxysilane for impregnating cement-bonded fibrous building components
US5393330A (en) * 1993-06-30 1995-02-28 Osi Specialties, Inc. Cationic emulsions of alkylalkoxysilanes

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2749588A1 (en) * 1996-06-10 1997-12-12 Rhone Poulenc Chimie AQUEOUS EMULSION OF SILICONE RESIN FOR HYDROFUGATION OF CONSTRUCTION MATERIALS
WO1997047569A1 (en) * 1996-06-10 1997-12-18 Rhodia Chimie Aqueous silicon resin emulsion for waterproofing building materials
EP2065431A1 (en) 2007-11-30 2009-06-03 Wacker Chemie AG Aqueous Dispersions of Organosilicon Compounds
DE102007047907A1 (en) 2007-11-30 2009-06-04 Wacker Chemie Ag Aqueous dispersions of organosilicon compounds
US8449666B2 (en) 2007-11-30 2013-05-28 Wacker Chemie Ag Aqueous dispersions of organosilicon compounds
US10829505B2 (en) 2016-04-20 2020-11-10 Dow Silicones Corporation Lithium alkylsiliconate composition, coating, and method of making same
WO2021126175A1 (en) 2019-12-18 2021-06-24 Wacker Chemie Ag Aqueous dispersions of organosilicon compounds

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